CVE-2024-27934: deno Use-After-Free — Exploit & Fix

Description

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Starting in version 1.36.2 and prior to version 1.40.3, use of inherently unsafe `*const c_void` and `ExternalPointer` leads to use-after-free access of the underlying structure, resulting in arbitrary code execution. Use of inherently unsafe `*const c_void` and `ExternalPointer` leads to use-after-free access of the underlying structure, which is exploitable by an attacker controlling the code executed inside a Deno runtime to obtain arbitrary code execution on the host machine regardless of permissions. This bug is known to be exploitable for both `*const c_void` and `ExternalPointer` implementations. Version 1.40.3 fixes this issue.

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CVSS v3.1 Score

8.4

HIGH

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-416 Use After Free

Affected Products

Vendor	Product	Versions
deno	deno	1.36.2 — 1.40.3

References

Advisories & Patches

https://github.com/denoland/deno/security/advisories/GHSA-3j27-563v-28wf https://github.com/denoland/deno/security/advisories/GHSA-3j27-563v-28wf

Exploits

https://github.com/denoland/deno/security/advisories/GHSA-3j27-563v-28wf https://github.com/denoland/deno/security/advisories/GHSA-3j27-563v-28wf

Frequently Asked Questions

What is CVE-2024-27934? +

Deno is a JavaScript, TypeScript, and WebAssembly runtime. Starting in version 1.36.2 and prior to version 1.40.3, use of inherently unsafe `*const c_void` and `ExternalPointer` leads to use-after-free access of the underlying structure, resulting in arbitrary code execution. Use of inherently unsafe `*const c_void` and `ExternalPointer` leads to use-after-free access of the underlying structure, which is exploitable by an attacker controlling the code executed inside a Deno runtime to obtain arbitrary code execution on the host machine regardless of permissions. This bug is known to be exploitable for both `*const c_void` and `ExternalPointer` implementations. Version 1.40.3 fixes this issue. It has a CVSS v3.1 base score of 8.4 (HIGH).

How severe is CVE-2024-27934? +

CVE-2024-27934 has a CVSS v3.1 score of 8.4 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2024-27934? +

CVE-2024-27934 affects products from deno, specifically: deno. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-27934? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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